>> Chapter 21, specifying
three-dimensional coordinates.
In this chapter, we're going to work
on understanding 3D drawing,
working with the 3D coordinates,
and working with the elevation and thickness,
creating a custom
User Coordinate System for 3D drawing.
Before, we were working always in
the x and y space or axis.
In this chapter, we are adding z-axis.
In this Figure 21.1, as you can see,
on the left image is
a top view or floor plan of a building,
and the right view is a perspective.
Working in three-dimensional environment.
So either you can open a template file as
acad3D or you can change
the workspace to three-dimensional space.
Here on AutoCAD,
there is a workspace
and next to the Quick Access view.
Drafting annotation,
it means two-dimensional drawing.
Switch that one to 3D modeling.
You can see the panels
and ribbons are changing.
If you don't have a workspace,
you can find this drop-down arrow
and look for the workspace.
We are now in the 3D modeling space.
Under view, you can
see viewport toolbars
and unsaved view,
or you can see in the isometric views;
Southwest isometric,
Southeast isometric, Northeast isometric.
Click on that one. We are
on the Northeast isometric.
And even the view cube,
you have a chance to switch the views.
In the 3D modeling,
I'm going back to Home tab,
we have three types of modeling; solid,
surface, mesh,
and we are planning to work on the
solid and mesh in this class.
Under Home, we have
x and y and additional z-axis.
Now we are on the World Coordinate System.
For example, if I draw
a box and change
the visual style conceptual,
I'm going to change the coordinate.
Here under the tab, there
is a coordinates panel.
If I change the coordinates to the front,
can you see the difference on
the direction of the x-axis,
and y-axis, and z-axis?
So that's how we
are changing the coordinates,
and it's called User Coordinate System.
Switching to the right, under Coordinates,
I'm going to change the coordinates to top.
So top is like
a World Coordinate System for us now.
So the origin is changing every
time. One more time.
Front, you can see the x, and y,
and z-axis, right, x and y,
and z-axis, and left,
top,
and the bottom.
So why do we need access
to change the coordinates?
The reason that we need to change
the coordinate is, for example,
if I'm planning to draw
something on the left view,
from the Home tab drawing panel circle.
When I move my mouse, on the left view,
I have a chance to draw that circle
exactly on the left view.
I'm going back to World Coordinate System.
I'm changing the visual style
to 2D wireframe and
now we are going to start working
on Exercise AB21-A DWG file.
So from Canvas, please download
a File AB21-A and open that file.
And also from the book,
you can see the steps for drawing
the
3D coordinates,
using 3D coordinates.
So I'm going to follow the steps
from this book on Page 664.
On desktop, I created ENT 135.
So here I have my DWG Bible book drawing.
There's AB21-A here.
I'm going to open File AB21-A.
It's an empty file.
So I'm going to save as this file
back to Assignment
21A-01.
Steps using 3D coordinates.
Open File AB21-A DWG from the Canvas site.
This exercise, assume that
you have a dynamic input turn
on set to the default of relative coordinate.
The drawing used
a two-dimensional environment.
It looks like three-dimension environment.
So I'm going back to two-dimension.
Save it as AB21-1 in your assignment folder.
Choose a home type,
drawing panel rectangular,
and create a rectangle.
Start a rectangle comment at
the specifying first corner rectangle.
Type 0,
0, 19.
Press "Enter".
At the specified other corner type
39, 15, "Enter".
This creates a rectangle 39 units
by 15 units wide.
That is 19 units above the x and y-plane.
Notice that you omit
the z-coordinate for the second corner.
Choose a home tab,
modify panel, copy to start.
We're going to copy
the rectangle two units
above the original rectangle.
So select the rectangle,
select object, press "Enter",
and type 0,
0, 2, "Enter".
Press "Enter" to get out of the command.
You have two rectangles but
because you are looking from
top, you see only one.
So we are going to
Home tab view panel
3D navigation dropdown list
and choose Southeast isometric.
Now you can see two rectangles.
If object snap is not turned on,
click on the "Object Snap".
Remember object snap?
Set the running object snap to endpoint.
I'm going to turn off the rest of them.
Start the line command and check on here.
We should be following Figure 21.6.
I'm in the Step 7,
going back to our figure drawing.
Start Home tab line.
From Point 1,
pick endpoint at Point 1.
So second point or specifying next point,
type pound, 0,
0, 0, "Enter".
Specifying next point, 1,
0, 0, "Enter".
Specifying next point, 0,
0, 21, "Enter" and "Enter".
We need to copy these three lines.
Press "Enter".
From the endpoint,
type 38, 0, 0, "Enter".
Means 38 units to the right.
I can just copy those two legs all
the way to the extraction,
to the y direction to back of the table.
So copy. Either I
can just copy from here to here
or I could just add 15 for
the coordinates and it would
copy the legs all the way to the back.
Actually, it's a piano bench.
To draw an open cover for the piano bench,
we need to start a line again, line.
Start at the endpoint at Point 2.
Here is a Point 2 from the book.
And specifying next point,
type 15 with the angle of
90 and the angle
of 45. Press "Enter".
And turn on the Ortho mode or F8.
Make sure you go straight all the
way and type 39,
is the same way of drawing a line.
And also, you can all the way
down and close this door
by finishing with the endpoint
of the left corner or Point 3 from the book.
The last line is going to be the bracing.
This line. So you're
going to have to start the line.
Starting point is going to be Number
4 to Number 3,
or you can use coordinates
of 15 with the angle of 20,
2 as a z-axis.
Press "Enter". As you see,
our drawing is in the three-dimensional view.
Don't forget to save your file.